Method for controlling multiple indoor air quality parameters

ABSTRACT

The present invention provides an improved method and system for controlling an HVAC system for managing multiple indoor air quality (IAQ) parameters. An acceptable range is defined for each of the IAQ parameter. The parameters are then monitored by sensors within a controlled space. The parameters may comprise temperature, humidity, smoke, radon, VOCs, carbon dioxide, carbon monoxide, particulates, hydrocarbons, oxygen, ozone, and odors. The invention maintains the IAQ parameters within their respective acceptable ranges by automatically manipulating certain HVAC system functions including heating, cooling, humidification, dehumidification, ventilation, addition or removal of materials or compounds which affect IAQ parameters, airflow volume and air recirculation. In one embodiment of the invention, a non-HVAC-specific venting system is used to augment HVAC adjustment of airflow volume and air recirculation. This may include bathroom, kitchen and attic venting systems as well as whole-home vacuum systems.

BACKGROUND

1. Technical Field

The present invention relates generally to a process or method for controlling HVAC systems, and more particularly to controlling HVAC systems according to multiple variables including but not limited to measurements of indoor air quality parameters.

2. Description of Related Art

Simple heating ventilation and air conditioning (HVAC) systems respond to or control merely one or two variables at a time. Temperature is the one most often controlled. When the environment is too hot or cold, a system turns on a heater, furnace, heat pump, or air conditioner based on the settings of a thermostat and adjusts the air temperature either upward or downward to match a set point and keep the air in a controlled space within a temperature range. Relatively sophisticated systems can be programmed to different set points or ranges at different times during a typical daily cycle.

HVAC systems typically control temperature with a single temperature controller or thermostat which has the single control input of dry bulb temperature and a single controlled output which is the run time of the equipment and in some cases, the recirculating air temperature. This equipment can have an effect on other variables such as humidity in the controlled space during operation. When moisture content is high, or when the thermostat does not sufficiently run the equipment because of low dry bulb conditioning requirements, the humidity can be excessively high. Also, during periods of high humidity and relatively warm temperatures in a controlled space, many air-handling units have sufficient capacity to cool the space, but are incapable of keeping the humidity at a sufficiently comfortable level. In such cases, a separate humidity control unit can be added to the system.

FIG. 1A shows a typical HVAC system with a rudimentary controller for a residential dwelling 110. With reference to FIG. 1A, an HVAC unit 140 pulls internal air into an inlet 106 and blows it through air conditioning openings 108 throughout the controlled space 102. The HVAC unit 140 usually attempts to control the temperature of the air in the controlled space 102 through the use of a temperature sensor 104 or thermostat and a feedback controller (not shown). Thus, at most, the HVAC unit 140 can heat or cool the air as it recirculates through the controlled space. Relatively small volumes of air may also enter or leave the controlled space 102 through openings 116 to the outside 150 such as windows or doors or other leaky openings.

Some residential and commercial HVAC units offer a slight improvement over such rudimentary circulation by supplementing recirculated air with an inlet stream of fresh air. In this way, multiple air quality variables may be adjusted by controlling the relative amount of inlet or fresh air flowing into the HVAC system. Certain HVAC systems, including those in automobiles, commonly include an inlet air controller such as a movable valve or shutter (referred to herein simply as an inlet air valve) that is positioned to control what proportion of the inlet air is drawn from inside and outside the controlled space. In a typical application, a system controller positions the air inlet valve to optimize system efficiency and occupant comfort, and an occupant is permitted to override the normal control when indoor air recirculation or outside air ventilation is desired. For example, air recirculation may be used to limit the intrusion of polluted outside air, or outside air may be used to purge the controlled space of smoke or odors. However, occupants frequently fail to manually correct the inlet air valve to accommodate the prevailing conditions in the controlled space. A need exists for a control system that measures IAQ parameters in the controlled space and makes adjustments automatically.

FIG. 1B shows a typical residential HVAC unit with just such a limitation. With reference to FIG. 1B, an HVAC unit 140 pulls inside air into an inlet 106, combines it with fixed volume of fresh outside air taken from an outside air inlet 112, and blows it through air conditioning openings 108 throughout the controlled space 102. In addition, some HVAC systems purge some of the air in the controlled space 102 through an exhaust vent 114. Through the combination of adding fresh outside air and exhausting some stale air, the HVAC system 140 reduces build up of air quality contaminants. Simultaneously, an HVAC system 140 controls air temperature in the controlled space 102 through the use of a temperature sensor 104 and a feedback controller (not shown). The HVAC unit 140 blows a fixed ratio of recirculated air and fresh or makeup air throughout the controlled space. Such ratio can be adjusted for comfort conditions, efficiency, or seasonal changes and is not normally dynamically controlled in real time to adjust for variations in air quality parameters. Likewise, no dynamic real time adjustment is made for changes in the amount of air that enters or leaves through windows and doors such as when occupants enter or leave the controlled space.

In addition to the limitation of controlling just one or two variables, all HVAC systems have a maximum volume of air for ventilation through the controlled space. There is no systematic means to supplement this ventilation volume. While other ventilation systems exist in the house, for example bathroom and kitchen ventilators, they are not integrated into a system which controls ventilation levels for the building.

There have been some attempts at detecting and controlling a single pollutant or environmental constituent depending on certain conditions. For example, U.S. Pat. No. 6,916,239 issued to Siddaramanna et al. on Jul. 12, 2005 (“patent '239”) discloses a method of controlling carbon dioxide levels in a controlled space by changing the volume of air circulated, depending on the number of human occupants in the controlled space. The '239 patent discloses a method to control both carbon dioxide levels and air temperature within a controlled space. Outside air is injected into the controlled space when predicted carbon dioxide levels rise. The carbon dioxide levels are predicted based upon a count of people entering or exiting a controlled space. An alternative method of controlling carbon dioxide levels in a space uses single or multiple carbon dioxide sensors in conjunction with a controller to adjust the amount of outside air injected to keep carbon dioxide levels within a desired range.

Some newer HVAC systems control the indoor humidity within certain limits in addition to temperature. U.S. Pat. No. 6,826,920 issued to Wacker on Dec. 7, 2004 (the “'920 patent”) discloses a humidity controller integrated with a constant volume air-handling unit. The '920 patent discloses a system having an actuator controlling a mixed air damper and actuator controlling both an outdoor air intake damper and an indoor air exhaust damper. It also teaches the use of humidity and temperature sensors placed outdoors and within the controlled space, wherein humidity may be controlled by slowing down the movement of air across the cooling coil of the air-handling unit.

Despite the existence of a variety of improved HVAC systems, improved sensors, and improved control systems, there remains a need to control HVAC systems according to multiple variables including those associated with air quality within a controlled space, not just the “comfort” variables of temperature and humidity. A need exists to simultaneously control temperature, humidity, odors, and the level of inside air constituents and pollutants, as well as a programmed set of responses to changes in a variety of environmental variables. Furthermore, it would be desirable to independently control such variables in a plurality of controlled space compartments. The present invention fills these goals and others as detailed more fully below.

SUMMARY OF THE INVENTION

The present invention provides an improved method and system for controlling an HVAC system for managing multiple indoor air quality (IAQ) parameters. An acceptable range is defined for each of the IAQ parameter. The parameters are then continually monitored by sensors within a controlled space. The parameters may include temperature, humidity, and levels of smoke, radon, VOCs including aldehydes, carbon dioxide, carbon monoxide, particulates, oxygen (O₂), ozone (O₃), and odors. The invention maintains the IAQ parameters within their respective acceptable ranges by automatically manipulating certain HVAC system functions including heating, cooling, humidifying, dehumidifying, the addition or removal of materials or compounds that affect IAQ parameters, airflow volume and air recirculation.

In one embodiment of the invention, non-HVAC-specific venting systems are used to augment HVAC adjustment of airflow volume and air recirculation. This may include bathroom and kitchen exhaust vents, attic fans as well as whole-home vacuum systems.

In another embodiment, an improved thermostat is disclosed that includes the additional sensors. This allows for a central point of control. The thermostat may include sensors for particulates, radon, VOCs, carbon dioxide, carbon monoxide, oxygen, ozone, hydrocarbons, smoke and odors.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will be best understood by reference to the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings, wherein:

FIG. 1A is a schematic view of a controlled indoor space showing air temperature control according to the prior art;

FIG. 1B is a schematic view of a controlled indoor space showing air temperature control along with fresh air input and air exhaust according to the prior art;

FIG. 2 is a schematic view of a controlled indoor space showing elements of an improved method to control indoor air quality according to a first embodiment of the present invention;

FIG. 3 is a schematic view of a controlled indoor space showing elements of an improved method to control indoor air quality according to a second embodiment of the present invention;

FIG. 4 is a response matrix or table showing possible actions taken in response to changes in at least one indoor air quality parameter or constituent;

FIG. 5 shows alternate embodiment of the present invention in which the traditional airflow and venting passages of the HVAC system are supplemented with additional venting systems commonly found in homes;

FIG. 6 illustrates the optimization relationships between IAQ components and conditions for which the HVAC system must compensate; and

FIG. 7 illustrates a controller that incorporates thermostat controls and IAQ sensors and controls as well.

DETAILED DESCRIPTION

While the invention is described below with respect to a preferred embodiment, other embodiments are possible. The concepts disclosed herein apply equally to other processes and methods to control indoor air quality (IAQ) parameters. in a controlled space. These IAQ parameters include comfort components such as temperature and humidity and traditional IAQ components such as levels of radon, VOCs including aldehydes, carbon dioxide, carbon monoxide, particulates, oxygen (O₂), ozone (O₃) and odors.

The present invention is an improved method for controlling IAQ parameters by controlling airflow throughout an enclosed or controlled space, including individual zones within such space. FIG. 2 illustrates one embodiment of the elements used in the present invention wherein a dwelling or living space comprises three zones. With reference to FIG. 2, air is recirculated through a controlled space divided into compartments, rooms, or zones. As in most dwellings, there is some commingling of air between a first zone 202, a second zone 204, and a third zone 206 as shown by the arrows. Air flows counter-clockwise from an HVAC unit 240 through air passageways into each zone 202, 204, 206 and returns to the HVAC unit 240 through return vents 242, 244, 246 from each room. Baffles 222, 224, 226 control the flow of air into each of the respective zones 202, 204, 206. Sensors 212, 214, 216 in each of the zones 202, 204, 206 provide feedback signals to the controller in the HVAC unit 240 or alternatively to a controller 250 located within the space. The controller, which is located in the space, would also communicate with the HVAC unit 240. Communication can be through wires or alternatively through wireless means.

An outside sensor 218 allows the HVAC system to determine the quality of the outside air 150. Fresh or outside air 150 enters the controlled space through a separate intake vent. An intake baffle 230 in conjunction with an exhaust baffle 228, control the relative amount of fresh air versus recirculated air in the system. Internal to the HVAC unit 240, one or more elements (not shown) provide a continuous range of overall airflow to the controlled space. Such range may extend from no airflow (off position) to a maximum of several volumes of controlled air space per unit time (e.g. ten volumes per hour).

Each sensor 212, 214, 216 may be a single sensor, a composite sensor or may represent multiple sensors that provide a feedback signal on a variety of air components and air conditions. Additionally, each sensor may be in the return duct leading back to the HVAC unit 240 from each of the zones 202, 204, 206. Such signals are used to control system components or variables to affect IAQ parameters.

The method of the present invention is illustrated with reference to FIG. 2 according to various scenarios. In a first scenario, when an IAQ parameter (e.g. VOC) enters a first zone 202, a first zone sensor 212 alerts the HVAC system 240, which responds by taking a variety of programmed actions. The HVAC system 240 increases the overall airflow within the controlled space and, if possible, also changes the relative amounts of airflow through the various zones 202, 204, 206.

The HVAC system 240 accomplishes this change by partially or fully closing a second airflow baffle 224 and a third airflow baffle 226 leading to the second zone 204 and third zone 206, respectively. The HVAC system 240 also increases the opening of a first airflow baffle 222 leading to the first zone 202. Finally, the HVAC system maximizes the use of fresh or outside air 150 into the controlled space. In this way, the pollutant is flushed as quickly as possible from the controlled space and the first zone 202. This example assumes that the outside or fresh air is lower in concentration of the pollutant. With reference to FIG. 2, the HVAC system can make adjustments based upon a reading from an outdoor sensor 218 regarding the amount of pollutant in the outside air 150.

In a second example, if the outside concentration of an IAQ parameter is above an unacceptable level, and if a first zone sensor 212 detects an increase of this IAQ parameter, the HVAC system 240 responds differently. In this second scenario, the HVAC system 240 maximizes recirculation of air within the controlled space to minimize the chance of the outside IAQ parameter from entering the system. The HVAC system 240 does this by closing an exhaust baffle 228 and closing an input air baffle 230. It may also optionally slow the overall flow of air throughout the controlled space and if appropriate, turn on a device within the system which removes the IAQ parameter of concern. If the second and third sensors 214, 216 in the second and third zones 204, 206, respectively, detect lower amounts of this IAQ parameter, the HVAC system 240 circulates more air through the first zone 202 relative to the second zone 204 and third zone 206 to flush out the IAQ parameter from the first zone 202. As before, this is accomplished by changing the relative positions of the airflow baffles 222, 224, 226. Once the indoor sensors 212, 214, 216 indicate that the level of IAQ parameter has declined to below an acceptable limit, the HVAC system returns to normal operation.

In a third scenario, if the second sensor 214 detects a high level of carbon dioxide, the HVAC system 240 increases the overall airflow to the entire controlled space and increases the relative amount of fresh air injected into the controlled space. If the second sensor 214 detects a high level of VOCs, the HVAC system 240 turns on a device within the system to reduce the VOCs by absorption, adsorption, conversion or other means. The HVAC system 240 also responds by increasing the circulation of fresh air into the controlled space as previously described, and increasing the flow of air into the second zone 204 if possible.

In a fourth scenario, if the third sensor 216 detects a relatively high level of particulates, the HVAC system 240 turns on an internal filtration system (not shown) to filter out the air-borne particulates. Such internal filtration system may be within the air ducts returning to the HVAC system 240, or may be a separate airflow system in fluid communication with one or more zones of the controlled space. In addition, the HVAC system 240 may increase the airflow to the third zone 206 where the high level of particulates is found or to the entire controlled space so as to keep particulates airborne and exposed to the filtration system. In each scenario the sensors can communicate with a centrally located controller 250, like the thermostat shown in FIG. 7. The connection can be by wireless or wired network.

FIG. 3 is a second embodiment of the elements used in the present invention wherein similar three zones are found within a dwelling. In this configuration, air is circulated through a controlled space divided into three zones 302, 304, 306. In this dwelling 110, as mentioned in regard to FIG. 2, there is some commingling of air between a first zone 302, a second zone 304, and a third zone 306 as shown by the arrows. Unlike the embodiment in FIG. 2, air flows counter-clockwise from an HVAC unit 340 through individual air passageways into each zone 302, 304, 306. Air circulated in this manner returns in separate air return lines to the HVAC unit 340 through individual return vents 342, 344, 346 in each room. Baffles 222, 224, 226 may be used to control the flow of air into each of the respective zones 302, 304, 306. However, as shown in FIG. 3, through the use of separate air lines, these airflow baffles 222, 224, 226 are not required and airflow into each zone 302, 304, 306 may be controlled directly within the HVAC system 340.

With reference to FIG. 3, sensors 212, 214, 216 in each of the zones 302, 304, 306 provide an electronic feedback signal to the controller in the HVAC unit 340. When one of the sensors detects the presence of a contaminant, the HVAC system 340 responds. For example, when the second sensor 214 detects an abnormally high level of VOCs, the HVAC system 340 responds by changing the airflow in the second zone 304 and possibly turning on a device within the system, which removes VOCs. Specifically, the HVAC system 340 increases the quantity of airflow entering and exiting the second zone 304. The HVAC system 340 may also increase the airflow or air pressure in the first zone 302 and the third zone 306 so that the overall net flow of air is into the second zone 304 and out through the second return duct 344 to the HVAC system 340. With individual air passages into each zone, the HVAC system 340 may blow recirculated air into the first zone 302 and the third zone 306, and may blow fresh outside air 150 into the second zone 304. The HVAC system 340 may blow heated air into the first zone 302 and third zone 306 and may blow cool air into the second zone 304 so as to further limit the diffusion of contaminant out of the second zone 304. Alternatively, if a high level of carbon monoxide is detected within the controlled space the HVAC system 340 may slow or stop air recirculation, increase ventilation and/or set off an alarm to alert the occupants of the controlled space of the presence of unacceptable levels of carbon monoxide.

The HVAC system 340 takes corrective action until a detectable contaminant has reached an acceptable level. The HVAC system 340 may take other simultaneous corrective actions to maintain the other controlled variables within desired ranges. For other disturbances, the HVAC system 340 makes specific, individually tailored corrective actions depending on the identity of the contaminant or type of disturbance.

FIG. 4 illustrates the various actions 400 taken by an HVAC system according to detected changes in dependent variables according to one embodiment of the invention and any number of scenarios such as those previously presented. FIG. 4 is by way of illustration and should not be construed as a limitation on the functions of the present invention. An HVAC controller 402 measures IAQ parameters 404. These measurements are conveyed to the HVAC system 406. For comfort components, the system may perform as a traditional HVAC system 408. However, for the measured IAQ components 410, the system will perform in other ways to mitigate and control the IAQ parameters. For high CO₂ or radon measurements 412, the HVAC system will open ventilation dampers 414 and allow more fresh air into the controlled space. The system may also activate a whole house vacuum system, which is typically driven by a blower located in the home's garage or basement. Alternatively, or in supplement thereof, the system can activate the kitchen, bath or laundry exhaust systems. The controller 402 will activate the vacuum, which will then vent the CO₂ or radon from the controlled spaces having access ports to the whole home vacuum system. Covers over the ports may be opened to create access between the controlled space and the vacuum system. For this system to be more effective, the vacuum system could be vented to the outdoors. In the event that the measured IAQ parameters indicate high particulates 420, then the fan may be run continuously through filtration media 422 until the particulate count reaches an acceptable level. Alternatively, the system may simply shut-down if the level of particulates indicates a fire. In the case of high volatile organic compounds (VOCs) 430, the system may again ventilate the controlled space to the outside. It may also activate an air cleaner 432 such as a PCO (photocatalytic oxidation) device that uses ultraviolet light to break down the VOCs.

FIG. 5 shows another embodiment of the present invention in which traditional airflow and venting passages of the HVAC system are supplemented with additional venting systems commonly found in homes. In addition to HVAC air ducts, most homes include several additional air venting systems associated with specific functions. The two most common are kitchen exhaust systems and bathroom ventilation systems. In addition, in some geographical areas, fans are sometimes installed in homes to exhaust indoor air to the attic for whole house cooling at night. Less common is a whole house vacuum system, which provides a centralized vacuum that may be accessed from multiple vent outlets throughout the house.

The present invention is able to complement the ventilation capabilities of the HVAC system with these non HVAC-specific ventilation systems. Referring to FIG. 5, the first zone 502 in the controlled space may be the kitchen, which includes a vent 510. The third zone 506 might be a bathroom with an exhaust vent 512. If the home in question has a whole house vacuum system, it is likely to have airflow outlets 514, 516, 518 in each room (zone) leading to a common outflow vent 520.

The HVAC system 540 is able to control these additional ventilation systems in order to supplement and fine tune the functions of the HVAC baffles and airflow vents. For example, if toast is burned in the kitchen, it may be most desirable to turn on the kitchen exhaust fan in conjunction with supplying additional air to the zone including the kitchen using the HVAC system 540. If a fire occurs however, and there is an acute increase in smoke, VOCs or carbon monoxide that the HVAC ventilation airflow paths alone cannot compensate for within an acceptable time frame, the system 540 may simply be programmed to shut down. A shut down could also be initiated by a signal from a fire detector or a security system. Similar to the system shown in FIG. 2, the non-HVAC venting systems can be controlled by a centrally located controller 550. The connection between the controller and the venting system can be wired or wireless.

FIG. 6 illustrates the optimization relationships between IAQ components and comfort components for which the HVAC system must compensate. When dealing with multiple parameters, some of which require different compensatory actions on the part of the HVAC system, there must be a constant balancing of one parameter against another. FIG. 6 shows a simplified graph that covers four parameters: carbon dioxide, VOCs, temperature, and humidity. Additional parameters may also be included, but for simplicity of illustration, the present example is limited to four.

An optimal range is established for each parameter. The control algorithm for the HVAC system attempts to keep all parameters within their respective optimal ranges. If any of the parameters, such as VOCs 604 and temperature 606, begin to move out of this range, the HVAC system will compensate to bring it back to optimal. In the example depicted in FIG. 6, both carbon dioxide 602 and humidity 608 are beyond their designated maximum, which would trigger the HVAC system to adjust them. The HVAC system continually balances the parameters against each other in order to keep them within this range, and may rely on supplemental venting provided by non-HVAC airflow paths as described above. In certain circumstances, it might be difficult to keep all parameters within guidelines at all times. To address such conflicts, a hierarchy of control can be establish based on the relative importance of each parameter. For example, one response to high CO2 levels is to increase ventilation. Yet, in the summer, this might also result in high humidity.

This invention also includes an improved HVAC controller 700 as shown in FIG. 7. The controller may look like a normal thermostat having a case 702 and a display 704. A series of sensors 706 may be located in the case 702. Alternatively, the sensors can be located throughout the controlled spaces as shown in FIGS. 2 and 5. The sensors could be modular so that a select set of sensors may be used. For example, this HVAC controller might have temperature and relative humidity sensors, CO₂ and radon sensors, a particulate sensor and a VOC sensor. For a simpler controller, maybe only a CO₂ sensor is included. The display includes readings for temperature 708, and relative humidity 710. For these values, users are well accustomed to seeing and understanding numerical values. However, for a factor such as CO₂, a user may be better served with a bar graph showing acceptable ranges and a current reading located on that bar 712. The same is true for a contaminant such as radon. For other IAQ parameters, such as particulates and VOCs, it may be better to have a set of potential ranges such as low, medium and high 714. The present HVAC controller is flexible and may provide for each of these forms of readout.

The foregoing discussion of the invention has been presented for purposes of illustration and description. Further, the description is not intended to limit the invention to the forms disclosed herein. Consequently, variation and modification commensurate with the above teachings, within the skill and knowledge of the relevant art, are within the scope of the present invention. The embodiment described herein and above is further intended to explain the best mode presently known of practicing the invention and to enable others skilled in the art to use the invention as such, or in other embodiments, and with the various modifications required by their particular application or uses of the invention. It is intended that the appended claims be construed to include alternate embodiments to the extent permitted. 

1. A method for using a heating ventilation and air conditioning (HVAC) system to control indoor air quality (IAQ), the method comprising the steps of: (a) setting an acceptable range for each of a plurality of IAQ parameters; (b) measuring said IAQ parameters; and (c) controlling HVAC functions to maintain at least one of said IAQ parameters within its respective acceptable range.
 2. The method of claim 1, wherein the IAQ parameters include at least one of the following: volatile organic compounds (VOCs); carbon dioxide; carbon monoxide; oxygen; ozone; radon; smoke; odors; particulates, and hydrocarbons.
 3. The method of claim 1, further comprising automatically controlling a non-HVAC-specific venting system to augment HVAC adjustment.
 4. The method of claim 3 wherein the non-HVAC-specific venting system comprises a bathroom exhaust vent.
 5. The method of claim 3 wherein the non-HVAC-specific venting system comprises a kitchen exhaust vent.
 6. The method of claim 3 wherein the non-HVAC specific venting system comprises a laundry exhaust vent.
 7. The method of claim 3 wherein the non-HVAC-specific venting system comprises a whole-house vacuum system.
 8. The method of claim 3 wherein the non-HVAC specific venting system is an attic fan.
 9. The method of claim 1 wherein a measured IAQ parameter is a high CO2 and the controlled HVAC function is increased ventilation.
 10. The method of claim 1 wherein a measured IAQ parameter is a high CO and the controlled HVAC function is increased ventilation.
 11. The method of claim 1 wherein a measured IAQ parameter is a high radon and the controlled HVAC function is increased ventilation.
 12. The method of claim 1 wherein a measured IAQ parameter is a high particulate level and the controlled HVAC function is increased circulation and filtration.
 13. The method of claim 1 wherein a measured IAQ parameter is a high particulate level and the controlled HVAC function is increased circulation.
 14. The method of claim 1 wherein a measured IAQ parameter is a high particulate level and the controlled HVAC function is shutting down circulation.
 15. The method of claim 1 wherein a measured IAQ parameter is a high VOC level and the controlled HVAC function is ventilation.
 16. The method of claim 1 wherein a measured IAQ parameter is a high VOC level and the controlled HVAC function is increased ventilation.
 17. The method of claim 1 wherein a measured IAQ parameter is a high VOC level and the controlled HVAC function is air purification.
 18. The method of claim 1 wherein control of an HVAC function is based on a hierarchy of control.
 19. A heating ventilation and air conditioning (HVAC) control system that manages indoor air quality (IAQ), the control system comprising: (a) a controller coupled to sensors that measure said IAQ parameters and having a memory to store settings for an acceptable range for each of a plurality of IAQ parameters; (b) a processor that adjusts HVAC functions to maintain at least one of said IAQ parameters within its respective acceptable range; and wherein said HVAC functions may include heating, cooling, humidifying, dehumidifying, ventilating, the addition or removal of materials or compounds that otherwise affect IAQ parameters, airflow volume, and recirculation of air.
 20. The control system according to claim 19, wherein the IAQ parameters include at least one of the following: volatile organic compounds (VOCs); carbon dioxide; carbon monoxide; oxygen; ozone; radon; smoke; odors; particulates, and hydrocarbons.
 21. The control system according to claim 19, wherein the control system also automatically controls a non-HVAC-specific venting system to augment HVAC adjustment of airflow volume and air re-circulation.
 22. The control system according to claim 21, wherein said non-HVAC-specific venting system comprises a bathroom exhaust vent.
 23. The control system according to claim 21, wherein said non-HVAC-specific venting system comprises a kitchen exhaust vent.
 24. The control system according to claim 21, wherein said non-HVAC-specific venting system comprises a whole-house vacuum system.
 25. The control system according to claim 21, wherein said non-HVAC-specific venting system comprises an attic fan.
 26. A controller for use with an HVAC-system comprising: (a) at least one IAQ sensor; and (b) a control circuit coupled to both the thermostat and IAQ sensor that produces an output in response to an input from either.
 27. The controller of claim 26 further comprises: (c) a sensor for measuring temperature.
 28. The controller of claim 27 further comprises (d) a display for displaying a temperature and an IAQ measurement.
 29. The controller of claim 28 wherein said display provides a numerical read-out.
 30. The controller of claim 28 wherein said display provides a bar graph readout.
 31. The controller of claim 28 wherein said display provides a range readout.
 32. The controller of claim 26 wherein said at least one IAQ sensor comprises a particulate sensor.
 33. The controller of claim 26 wherein said at least one IAQ sensor comprises a CO₂ sensor.
 34. The controller of claim 26 wherein said at least one IAQ sensor comprises a VOC sensor.
 35. The controller of claim 26 wherein said at least one IAQ sensor comprises a CO sensor.
 37. The controller of claim 26 wherein said at least one IAQ sensor comprises a radon sensor.
 38. The controller of claim 26 wherein said at least one IAQ sensor comprises a hydrocarbon sensor
 39. The controller of claim 26 wherein said at least one IAQ sensor comprises a ozone sensor.
 40. The controller of claim 26 wherein said at least one IAQ sensor comprises an odor sensor
 41. A method for controlling indoor air quality (IAQ) parameters comprising the steps of: (a) sensing the levels of IAQ parameters (b) controlling non-HVAC venting systems to augment HVAC-venting systems.
 42. The method of claim 41 wherein the non-HVAC venting system comprises a bathroom venting system.
 43. The method of claim 41 wherein the non-HVAC venting system comprises a kitchen venting system.
 44. The method of claim 41 wherein the non-HVAC venting system comprises an attic venting system.
 45. The method of claim 41 wherein the non-HVAC venting system comprises a whole house vacuum system. 